<template>
  <view class="like-button">
    <!-- #ifdef APP-NVUE -->
      <list class="animate-wrap">
        <cell
          class="a-img" 
          v-for="(item,index) in viewList" 
          :key="item.elId" 
          :ref="item.elId"
          :style="{
            'right': site.x || site[0] + 'rpx',
            'bottom': site.y || site[1] + 'rpx'
          }">
          <image :style="{
            'width': imgWidth + 'rpx',
            'height': imgHeight + 'rpx'
          }" mode="widthFix" :src="item.src" :animation="item.animation"></image>
        </cell>
      </list>
    <!-- #endif -->
    <!-- #ifndef APP-NVUE -->
      <view class="animate-wrap">
        <view
          class="a-img" 
          v-for="(item,index) in viewList" 
          :key="item.elId" 
          :ref="item.elId"
          :style="{
            'right': site.x || site[0] + 'rpx',
            'bottom': site.y || site[1] + 'rpx'
          }">
          <image :style="{
            'width': imgWidth + 'rpx',
            'height': imgHeight + 'rpx'
          }" mode="widthFix" :src="item.src" :animation="item.animation"></image>
        </view>
      </view>
    <!-- #endif -->
    <view class="on-button">
      <image :src="src" mode="widthFix" :style="{
        'width': width + 'rpx',
        'height': height + 'rpx'
      }" v-if="!$slots.default" @click="handleClick"></image>
      <view class="el_like_btn" @click="handleClick">
        <slot></slot>
      </view>
    </view>
  </view>
  
</template>

<script>
	export default {
    props: {
      src: {
        type: String,
        default: '/static/logo.png'
      },
      showImgs: { // 显示图标路径
        type: Array,
        default: () => {
          return [
            ``,
            '/static/logo.png',
          ]
        }
      },
      duration: { // 动画效果时间
        type: Number,
        default: 5000
      },
      range: { // x 间隔幅度
        type: Number,
        default: 50
      },
      high: {
        type: Number,
        default: 360
      },
      width: { // 图标宽度
        type: Number || String,
        default: 52
      },
      height: { // 图标高度
        type: Number || String,
        default: 52
      },
      imgWidth: { // 图标宽度
        type: Number || String,
        default: 52
      },
      imgHeight: { // 图标高度
        type: Number || String,
        default: 52
      },
      throttle: { // 点击节流 ms
        type: Number,
        default: 200
      },
      site: { // x y 坐标 [x<Number>, y<Number>]
        type: Array || Object, 
        default: () => {
          return [30, 160] || { x: 30, y: 160 }
        }
      },
      large: { // 是否缩放冒泡
        type: [Number, Boolean],
        default: false
      },
      alone: {
        type: Boolean,
        default: true
      }
    },
		data() {
			return {
				viewList: [], // 渲染元素
        elId: 0, // 元素渲染id
				oldTime: 0, // 全局时间用于函数节流
        timer: null, // 定时器
        waitDeleteIndex: 0
			}
		},
    watch: {
    },
		methods: {
			handleClick (e) {
				// 函数节流
        let interval = e.timeStamp - this.oldTime
				if(interval < this.throttle) return null;
        this.oldTime = e.timeStamp
        let animation = {}
        // 创建animate配置
        // #ifdef APP-NVUE
				animation = weex.requireModule('animation')
        // #endif
				let randomImg = Math.floor(Math.random() * this.showImgs.length)
				let _item = {
					elId: 'el_likeicon_' + this.elId, // 生成元素ref
					src: this.showImgs[randomImg],	// 随机图标
					animation: animation, // 每个盒子动画
					x: Math.ceil(Math.random() * this.range),	// 方向间距
					q: Math.floor(Math.random() * 2), // 随机方向
				}
        
				// 动画
        let _abs = ['-', '']
        let _dirX = Number(_abs[_item.q] + _item.x)		// 随机的方向和间距
        let _dirY = this.high - Math.random() * 10
        // 生成DOM
				this.elId ++
        this.viewList.push(_item)
        // #ifndef APP-NVUE
        _item.animation = uni.createAnimation({
          duration: this.duration,
          timingFunction: 'ease-out',
        })
        setTimeout(() => {
          console.log('animation finished.')
          // 完成后事件回调
          this.$emit('finished')
          // 逐渐消失
          if (this.alone) {
            this.waitDeleteIndex ++
            this.onThrottle(this.deleteView, this.duration)
            return null;
          } else {
            // 完成动画后在n秒后清空
            clearTimeout(this.timer)
            this.timer = setTimeout(() => {
              this.viewList = []
            }, this.duration)
            return null;
          }
        }, this.duration)
        // #endif
        // 执行动画
        
        setTimeout(() => {
          this.$nextTick(() => {
            let _n = 1
            if (this.large) _n = typeof(this.large) === 'number' ? this.large : 2;
            // #ifndef APP-NVUE
            _item.animation.translateY(-_dirY).translateX(_dirX).scale(_n, _n).opacity(0).step()
            _item.animation = _item.animation.export()
            // #endif
            // #ifdef APP-NVUE
            let el = this.$refs[_item.elId][0];
            clearTimeout(this.timer)
            _item.animation.transition(el, {
              styles: {
                transform: `translate(${_dirX}rpx, -${_dirY}rpx) scale(${_n}, ${_n}])`,
                transformOrigin: 'center center',
                opacity: 0
              },
              duration: this.duration, // ms
              timingFunction: 'ease-out',
              delay: 0 // ms
            }, () => {
              console.log('animation finished.')
              // 完成后事件回调
              this.$emit('finished')
              // 逐渐消失
              if (this.alone) {
                this.waitDeleteIndex ++
                this.onThrottle(this.deleteView, this.duration)
                return null
              } else {
                // 完成动画后在n秒后清空
                clearTimeout(this.timer)
                this.timer = setTimeout(() => {
                  this.viewList = []
                }, this.duration)
              }
            })
            // #endif
          })
        }, 0)
        // 点击立即触发组件事件
        this.$emit('handleClick', this.elId)
			},
      deleteView () {
        this.viewList.splice(0, this.waitDeleteIndex)
        this.waitDeleteIndex = 0
      },
      onThrottle (fn, delay) {
        let verifi = true
        return (function () {
          if (!verifi) return false;
          verifi = false
          setTimeout(() => {
            fn()
            verifi = true
          }, delay)
        })()
      }
		}
	}
</script>

<style lang="scss">
	.a-img {
		position: fixed;
	}
</style>
